Disposable underpants, such as child&#39;s training pants and the like

ABSTRACT

A disposable underpant (10, 10&#39;) comprising a front panel (11) and rear panel (12) joined together along side seams (13) to provide a three-dimensional garment having a pair of elasticized leg openings (14) and an elasticized waist opening (15), and including a bodyside liner (16), outer cover (17) and absorbent batt (18) therebetween, in which the outer cover (17) has an inner layer (30) of plastic material and an outer layer (31) of nonwoven fibrous material.

This application is a continuation-in-part of application Ser. No.690,351, filed Jan. 10, 1985.

TECHNICAL FIELD

This invention relates generally to the field of disposable underpantshaving elasticized leg and waist openings, particularly disposablechild's training pants and similar garments.

BACKGROUND ART

Disposable diapers, as is well known, now find wide-spread use forinfant care and have generally replaced the use of cloth diapers. Thetypical disposable diaper is a three-layer composite structurecomprising a liquid permeable bodyside inner liner, a liquid impermeableouter cover and an absorbent batt sandwiched between the liner and thecover. Materials now in general use for the three principal elements ofa disposable diaper include various types of nonwoven fabrics for thebodyside liner, a thin thermoplastic film for the outer cover andcellulosic fluff for the absorbent batt.

Disposable diapers of the type presently on the market are flatopen-sided garments that are intended to be fit about an infant by aparent while the infant is lying down. The rear panel of the diaper isplaced underneath the infant, and the front panel drawn between theinfant's legs, after which the sides are overlapped and held together bypressure sensitive adhesive tape. A diaper is meant for use when thechild is young and dependent upon a parent for this essential purpose.

The popularity of disposable diapers has led us to believe there is ademand for a disposable underpant, such as a disposable training pantthat can be used when a child grows out of a diaper. Diapers aretypically used with infants up to about fifteen months old. When a childreaches an age in the range of about fifteen to thirty months, however,a parent generally desires to start toilet training so that the childcan become independent of a parent. The training pant is intended foruse when the child has reached an age at which he or she is ready tograduate to an underpant type of garment as a replacement for disposablediapers previously used. Thus, a suitable training pant must be agarment having closed sides so that a child can raise and lower it asnecessary without requiring the aid of a parent. At the same time, atraining pant must provide features of liquid and solid absorbency andprevent leakage of the waste fluids.

Cloth training pants, although widely used, have disadvantages. Currentcloth training pants have very little absorbency and often must be usedwith exterior rubber or plastic pants. When a child wets a clothtraining pant, most often all of the child's clothes must be changed.Further, if a child has a bowel movement, it is difficult to remove acloth pant without making a mess, and the pant must be soaked andbleached. All of these factors can make the toilet training processfrustrating for both child and parent.

In addition, it is believed that the psychology of the toilet trainingstage is such that the child should perceive he or she is graduating toa garment that is different than a disposable diaper. The requirementsfor a disposable underpant such as a training pant are notsatisfactorily met by the constructions of disposable diapers ascurrently known in the art. In this connection, for example, the typicaldisposable diaper, as stated previously, has an outer layer comprising aliquid impermeable sheet of plastic film. Various techniques have beenused to give the plastic sheet the feel and appearance of texture, butthe exterior of the garment has a plastic feel or appearance which isclosely associated with the concept of a diaper but would beinappropriate for a disposable training pant. Since the purpose of atraining pant is to encourage the child to make the transition fromdiapers to washable or reusable cloth underpants, it is important that adisposable training pant simulate a cloth underpant as much as possible.

The need for a disposable training pant or similar underpant capable ofmeeting the demand for this type of garment has been the impetus for thedevelopment of the present invention.

SUMMARY OF THE INVENTION

Our present invention provides a disposable underpant, particularly adisposable training pant, comprising a three-dimensional garment havingclosed side seams, an elasticized waist opening and elasticized legopenings, and including a bodyside liner and outer cover with anabsorbent batt sandwiched therebetween, wherein the outer cover is a twolayer composite material providing the dual characteristics of liquidimperviousness and a clothlike appearance. This structure provides adisposable undergarment which is perceived as protective underwear for achild rather than a diaper associated for use by an infant.

An undergarment to be suitable for use in toilet training children or byincontinent children or adults should comprise (a) a nonwoven fabriccover having a front portion, a rear portion and a crotch portionconnecting the front and rear portions, both side margins of the frontportion being joined to respective side margins of the rear portion soas to define a three-dimensional undergarment having a pair of legopenings and a waist opening; (b) a liquid pervious inner liner and anabsorbent batt between the liner and the fabric cover, a first elasticmeans extending about one leg opening, a second elastic means extendingabout the other leg opening, and a third elastic means extending aboutthe waist opening.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a disposable underpant according to thepresent invention;

FIG. 2 is a side perspective view of the disposable underpant of FIG. 1;

FIG. 3 is a horizontal sectional view of the disposable underpant ofFIG. 1;

FIG. 4 is a partial horizontal sectional view similar to FIG. 3illustrating an alternate form of side seam for the disposable underpantof FIG. 1;

FIG. 5 is a plan view, with portions broken away illustrating a flatblank as suitable for producing the underpant of FIG. 1;

FIG. 6 is a plan view, with portions broken away, illustrating anotherform of flat blank suitable for producing the underpant of FIG. 1;

FIG. 7 is a partial sectional view illustrating one form of elasticizedleg and/or waist opening of the underpant of FIG. 1;

FIG. 8 is a partial sectional view illustrating another form ofelasticized leg and/or waist opening for the underpant of FIG. 1; and

FIG. 9 is a side perspective view of an alternate form of the disposablepanty of FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

FIGS. 1 and 2 illustrate, in front and side perspective viewsrespectively, a disposable underpant 10 constructed in accordance withthe present invention. The underpant 10 includes a front panel 11 and arear panel 12 joined together alongside seams 13 to form athree-dimensional garment with closed sides having a pair of legopenings 14 and a waist opening 15. Referring now to FIG. 3, theunderpant 10 includes a moisture pervious bodyside liner 16, a moistureimpervious outer cover 17, and an absorbent batt 18 positioned betweenthe liner 16 and outer cover 17. The absorbent batt may be secured toeither the bodyside liner or the outer cover, or both, by any suitablemeans well known in the art such as lines or other patterns of adhesive,pressure sensitive tapes, heat seals, sonic seals, etc.

Referring again to FIG. 1, the waist opening 15 of the underpant 10 issurrounded by a circumferential elasticized band 20 and each leg opening14 is surrounded by a circumferential elasticized band 21. Suitableconstructions for the elasticized bands 20 and 21 are described infurther detail later in this description.

The bodyside liner 16 can be any flexible porous sheet which passesfluids therethrough, i.e. a moisture pervious material, to be absorbedby the absorbent batt 18. The liner may comprise a nonwoven web or sheetof polyolefin fibers, such as polypropylene or polyethylene, orpolyester fibers; a web of spun bonded polypropylene, polyethylene orpolyester fibers; a web of rayon fibers; a bonded carded web ofsynthetic or natural fibers, or a mixture of synthetic and naturalfibers, and the like. Further the liner 16 may also comprise a plasticfilm which is perforated or apertured to obtain the desired degree ofmoisture perviousness, and may also comprise an expanded plastic webbingmaterial or a scrim material. The bodyside liner 16 preferably is madeof a material which will feel soft and comfortable against the skin ofan infant or adult.

The absorbent batt 18 may comprise any suitable material capable ofabsorbing and retaining waste fluids that pass through the liner 16.Thus, the absorbent batt may comprise cellulosic material such as anair-formed batt of wood pulp fibers, commonly known as "fluff"; a battof melt blown synthetic fibers, such as macrofibers or microfibers, ofpolypropylene, polyethylene, polyester and the like; a bonded carded webof synthetic or cellulosic fibrous materials; a composite of melt blownfibers, such as macrofibers or microfibers of polypropylene,polyethylene polyester or the like mixed with pulp fibers; or a blend offluff with staple textile fibers such as rayon and the like. Preferablythe batt should contain a high hardwood pulp content since thisincreases the fine microfiber pore structure in meltblown and similarbatts and therefore improves absorbency and liquid retention. The battmay comprise one or more layers or combinations of the foregoingmaterials.

Preferably, the batt may include compounds added to increase itsabsorbency. The material selected for the absorbent batt most usefullyhas an absorbent capacity in the range of about 30 to 550 grams ofsynthetic urine retained at 0.5 psi. For a disposable training pantintended for infant use after the diaper stage, the absorbent capacityof the batt is preferably in the range of about 350 to 500 grams ofsynthetic urine retained at 0.5 psi. Furthermore, it is desirable thatthe underpant 10 not present a diaper appearance and the absorbent batttherefore most usefully comprises a low bulk, high absorbency material.Preferably the batt will contain a three-dimensional dispersion ofparticles of water insoluble hydrocolloid polymer. The superabsorbent ispreferably dispersed uniformly in a three-dimensional configurationwithin the voids of the fibrous batt but in the region which is closestto the outer fabric cover, so that liquids contacting the batt penetratefreely within the batt to superabsorbent particles farthest from theskin of the wearer. There are several types of superabsorbent materialsthat are commercially available:

a. Grafted starch

b. Starch polyacrylic acid grafted copolymer

c. Grafted cellulose--(CMC) carboxy--methyl cellulose

d. Modified PVA (polyvinyl Alcohols), and preferably

e. Polyacrylic acid salts that are crosslinked to form absorbentpolymers such as Water-Loch J-500 (Acquakeep OSH) produced by Seitetsuin Japan.

Preferably the tensile strength of the absorbent batt should be fromabout 1.75 psi to about 5.00 psi. Also preferably, the burst strength ofthe absorbent batt should range from about 250 ergs/cm² to about 550ergs/cm² dry and from about 300 ergs/cm² to about 500 ergs/cm² wet.

Preferably the absorbent batt is formed having an outwardly bulgingcrotch portion. By contouring the batt in a manner providing the bulgein the crotch, the undergarment has a significantly greater amount ofabsorbent material in the crotch portion for improved protection fromleakage in an area where it is most needed. In addition, advantageouslydecreasing the amount and thickness of the absorbent material uponapproaching the periphery of the absorbent batt and the undergarment,i.e. in the longitudinal or end edges 54 and 53, provides increaseddiscreetness for the wearer. The undergarment will not have a tendencyto stick out during use. Additionally, it is preferable that theabsorbent batt be shaped such that when applied to the outer cover theabsorbent batt should be absent in the ear portion, i.e., the portionsof the outer cover lying outside the longitudinal line extending fromthe innermost portion of the curved leg opening, since the undergarmentdoes not require absorbency in this region and absence of the absorbentmaterial provides for a more discreet fit on the wearer and does notstick out during use.

Preferably, the undergarment is formed such that the traversemeasurement of the crotch section of the absorbent batt is less thanabout 3 inches. More preferably the traverse measurement of the overalldiaper is less than about 4 inches. The thickness in the bulge portionof the absorbent batt in the crotch portion is preferably about 1.5 to 5times the thickness of the absorbent material located in the front andrear portions of the absorbent batt. Preferably the thickness of theabsorbent batt in the crotch portion is about 2 times the thickness ofthe absorbent material in the front and rear portions. Preferably duringthe formation of the absorbent batt a web of absorbent is cut traverselywith a generally elliptically shaped cutout being made in the leg area.This leg area ellipse is folded over onto the top of the crotch portion.The ellipse is shown in FIG. 5 as 154; the ellipse is then placed atopthe absorbent batt in FIG. 6 in crotch region 156. Preferably thetraverse width of the absorbent material in the crotch portion is 1/4 ofthe sum of the widest traverse measurements of the front and rearportions. Forming an absorbent batt in this configuration eliminates theneed for a waste of the absorbent material while unexpectedly forming anabsorbent batt that provides additional absorbency in the needed areasand proper sizing about the waist.

Preferably the leg area ellipse is sized such that it covers at least 30percent, more preferably 50 percent of the absorbent batt and is biasedin size toward the front of the training pant.

In accordance with a highly preferred aspect of this invention, theouter cover 17 performs the dual functionality of providing moistureimperviousness and also providing a textile feel and look for theunderpant 10. For this purpose, referring now to FIG. 3, the outer cover17 comprises a two-layer composite material having an inner layer 30 andan outer layer 31. The inner layer 30 is a layer or stratum of plasticmaterial which provides a moisture barrier or liquid imperviousness.

Suitable plastic materials for the inner layer 30 are polyolefinpolymers such as polyethylene or polypropylene; polyolefin copolymerssuch as ethylene vinyl acetate, ethylene methyl acrylate or ethyleneethyl acrylate; polyvinyl chloride; nylon; or other thermoplasticmaterials capable of providing liquid imperviousness. The inner layer 30of the outer cover should provide a sufficient degree of liquidimperviousness to prevent or preclude waste fluids from striking throughor penetrating through the outer cover The outer layer 32 of the cover17 most preferably consists of a layer of nonwoven fibrous material.Materials suitable for the outer layer 31 include a spun-bonded nonwovenweb of synthetic fibers such as polypropylene, polyethylene or polyesterfibers; a nonwoven web of cellulosic fibers, textile fibers such asrayon fibers, cotton and the like, or a blend of cellulosic and textilefibers; a spun-bonded nonwoven web of synthetic fibers such aspolypropylene, polyethylene or polyester fibers mixed with cellulosic,pulp fibers or textile fibers; or melt blown thermoplastic fibers, suchas macrofibers or microfibers, of polypropylene, polyethylene, polyesteror other thermoplastic materials or mixtures of such thermoplasticmacrofibers or microfibers with cellulosic, pulp or textile fibers.

The inner layer 30 and outer layer 31 of the cover 17 are advantageouslybonded to one another, by any means appropriate for the specificmaterials selected for the two layers. The two layers can be laminatedusing heat or pressure or both heat and pressure. The two layers canalso be bonded with adhesive, heat sealing or ultrasonic sealing. Inaddition, thermoplastic polymeric material of the inner layer 30 can beextrusion coated onto the nonwoven outer layer 31. If desired, thetextile effect of the nonwoven outer layer 31 can be further enhanced byvarious embossing patterns.

FIG. 3 illustrates one form of side seams 13 for the underpant 10 thatis made by seaming together inturned contacting side edge portions ofthe outer layer 31 of the outer cover 17 of the front and rear panels.This provides a narrow fin seam, which can be made relatively narrowsuch as about 3/16 to 1/2 inch wide so as to minimize the amount of seamlocated inside the garment. The seams 13 between the inturned contactingside edge portions of the outer cover can be formed by any suitablemeans well known in the art appropriate to the specified materialemployed for the outer layer 31 of the cover; thus, sonic sealing, heatsealing, adhesive bonding, and the like are appropriate techniques. FIG.4 illustrates an alternate construction for the side seams 13 whereinside edge portions of the garment are overlapped and joined togetherwith an adhesive element 35 coated on both of its opposed surfaces withlayers 36 and 37 of pressure sensitive adhesive. In this alternateembodiment, a side edge portion of the bodyside inner liner 16 of therear panel 12 is bonded to a side edge portion of the outer layer 31 ofthe outer cover of the front panel 11 of the underpant 10. Sonic sealingand heat sealing techniques also can be used to bond the overlappedportions as shown in FIG. 4. Other side seam constructions effective toform a garment having closed sides can be employed to form the underpant10, and sewn side seams may be of interest such as for some types ofadult underpants.

An especially useful construction for the side seams 13 is a manuallytearable or tearaway seam. This can be obtained by bonding thecontacting side edge portions along a narrow bond within the side seamportions. A bond strength of about 2000 grams/inch of seam length (asmeasured on an appropriate instrument such as an Instron tensile tester)is suitable for providing a tearaway seam but which is also strongenough to hold the garment together. One way to make a seam of this typeis to bond the contacting side portions by suitably controlled sonicsealing along a narrow bond portion that is about 1/8" wide. A tearawayseam is a highly advantageous and preferred feature because a parent canmanually tear the side seams apart in order to remove the underpant froma child; this is particularly helpful when the underpant is quite soiledand removal in the normal fashion would be messy. A manually tearawayseam can be with both the inturned fin style seams illustrated in FIG. 3or the overlapped seam of FIG. 4. Another important consideration informing a strong bond which provides for a tearaway feature includesselection of a suitable material for the cover. Propropylene, ethylenevinyl acrylate, ethylene ethyl acrylate and ethylene methyl acrylate arepreferred. Polyethylene is not preferred but ethylene methyl acrylatecopolymers of ethylene may be used.

The side seams 13 in FIG. 3 are shown as incorporating another usefulstructural feature. The inturned contacting side edge portions of thegarment are joined together along a narrow bond portion 25 that isspaced from the free ends 26 of the side edge portions. This provides aside seam having a flap portion 27 inside the garment along which theside edge portions are not bonded together so as to be free of oneanother. Any bond portion, such as formed by sonic sealing, heat sealingor adhesive bonding, will be relatively stiff. The flap portion 27 actsas a cushion between a person's body and the stiff bond portion 25,thereby enhancing the comfort or wearability of the underpant 10. It hasbeen found that a bond portion about 1/16" to 1/8" wide and a flapportion about 1/8" to 3/8" wide are suitable for this purpose andprovide a fin seam that will not irritate an infant or adult wearing theunderpant 10.

The underpant 10 can be expeditiously manufactured from a blank cut to asuitable configuration. An appropriate blank 50 is illustrated in FIG.5. A sheet of material for the outer cover 17 is cut to an hourglassconfiguration having arcuate cutouts defining the leg openings of thegarment Absorbent batt 18, also cut to an hourglass configuration witharcuate leg cutouts, is placed on top of the outer cover in the desiredposition, and may be secured thereto by spaced parallel glue lines 51.Preferably the batt is shaped such that the extensions of the batt inthe areas outside longitudinal lines 258 and 260 in FIG. 6 extendingfrom the traverse edge of the inside crotch portion is limited. Anarcuate elastic means 52 is positioned around each leg cutout andpreferably, as explained below, positioned along the outer edge of thecover 17 along the cutout portion. Linear elastic means 53 arepositioned along each end 54 of the blank, which will form the elasticmeans for the waist portion of the finished garment. As indicated inFIG. 5, the elastic means 52 are positioned closely adjacent the nearbyedge of the absorbent batt so as to provide a form fitting panty type ofgarment instead of being spaced from the batt to have a web of materialbetween the elastic means and the batt as is common with some disposablediapers. Next, a sheet of bodyside inner liner 16, also cut to anhourglass configuration, is placed over the assembly of the outer coverand the batt. Both the liner 16 and cover 17 have superimposed marginalportions which project beyond the margin of the batt 18, and the linerand cover may be joined together with elastics 52 and 53 within thesuperimposed marginal portions. After being fully assembled, the blank50 is folded along its central transverse area and the sides of thefront and rear panels are seamed together as illustrated in FIG. 3 toform the finished underpant 10.

FIG. 6 illustrates a blank 60 suitable for producing underpant 10 havingside seams of the type illustrated in FIG. 4. Most elements of the blank60 are the same as those of the blank 50 and the corresponding elementsare therefore numbered with the same reference numerals. Blank 60includes an adhesive element 35 of two-side coated pressure sensitiveadhesive tape along each side edge portion 61 of the rear panel 12. Thus(see especially FIG. 4) adhesive layer 36 of each element 35 is adheredto a side marginal portion of the outer cover of the rear panel 12. Toproduce the underpant 10 from the blank 60, the blank is folded alongits transverse medial portion and the side edge portions 61 of the frontpanel are joined together to the layer 37 of pressure sensitive adhesiveof each element 35 in the manner shown in FIG. 4. The blank 60 alsoshows an alternate form of securing the absorbent batt 18 by use of twoside pressure sensitive adhesive elements 62 between the batt and outercover 17.

FIG. 9 illustrates an alternate system for construction of the underpantof the present invention wherein the underpant 10' includes a separatefront panel 11 and rear panel 12 that are joined together along centralcrotch seam 65. The remaining elements of the underpant 10' are the sameas in underpant 10 and the common elements are identified with thecorresponding reference numerals employed in FIG. 1. FIG. 9 representsan alternative method for constructing the underpants of the presentinvention as compared to making the underpants with the folded blanks 50and 60 of FIGS. 5 and 6.

FIGS. 7 and 8 illustrate particularly useful forms of elastic means foruse at the leg openings and waist opening of the underpant 10. Theelastic means constructions of FIGS. 7 and 8 are as described andclaimed in the commonly assigned co-pending patent application of Aleset al. entitled "Elastic Form-Fitting Closure Constructions forDisposable Garments," filed on Jan. 10, 1985, U.S. Ser. No. 690,348, thedisclosure which is incorporated herein by reference. As shown in FIG.7, elastic means 54 comprises a strip of elastic material 70 havingopposed surfaces 71 and 72, wherein surface 71 is bonded to closelyspaced bond points along an edge portion of the inner layer 30 of theouter cover 17 and surface 72 is bonded to an edge portion of theinterior surface of the bodyside liner 16. Further, the outer edges ofthe liner 16, cover 17, and elastic strip 70 are contiguous with oneanother. The elastic strip 70 is bonded to the liner 16 and cover 17along the entire area of its surfaces 71 and 72 when applied thereto inan elongated or stretched condition; upon retraction of the elasticstrip 70, micro-buckling of the outer cover between bond points resultsin an elasticized waist or leg opening which has a smooth yet finelyribbed or pleated appearance. FIG. 7 is a sectional view of theelasticized band 21 around the leg openings of the garment 10, and theelasticized band 20 around the waist opening can be of the samestructure.

The construction illustrated in FIG. 8 is similar to that of FIG. 7except that the elastic means 53 comprises a plurality of spacedparallel strands 75, 76 and 77 of elastic material, each strand having acircular cross section, as described and claimed in the commonlyassigned co-pending application of Ales et al. entitled "DisposableGarment with Multiple Strand Elasticized Openings," U.S. Ser. No.690,349, the disclosure of which is incorporated herein by reference.The elastic means construction of FIG. 8 can be used either for thecircumferential elasticized band 20 around the waist opening of theunderpant or the elasticized bands 21 around the leg openings 14 of theunderpant, or both; a presently preferred embodiment of the underpant 10is to employ the elastic means construction of FIG. 7 for thecircumferential band 20 about the waist opening and the elastic meansconstruction of FIG. 8 for the elasticized band 21 of the leg openingswith a good seal against leakage of fluids therethrough. The underpant10, however, can be constructed with other types of elasticized bands atthe waist opening and the leg openings, such as, for example, a strip ofelastic material intermittently bonded or sewn to either the outer cover17 or inner liner 16, or both, along the waist opening and leg openingsPreferably the elastic means about the waist and/or the legs is at leasttwo ribbons or ropes. Also, the elastic means can be contiguous with theouter edges of the liner and cover along the elasticized openings asshown in FIGS. 7 and 8, or it can be spaced inwardly thereof; in thelatter instance, it is preferred that the elastic means be spaced onlyslightly inwardly of the edges of the garment if it is desired to avoida gathered look about the leg and waist openings.

The tension measurement found useful was determined by stretching theleg opening to 10.5 inches for the small training pant (20-29 pounds)and 11.5 inches for the medium training pant (30-39 pounds), holding forfive minutes and then measuring the tension in grams. A similarprocedure was followed for the waist except the opening was stretched to18.5 inches for the small and 19.5 inches for the large. Thesestretching distances were determined as being the average leg and waistsize for the wearer of the small training pant and the medium trainingpant. Preferably the tension exerted by the elastic means in the legarea ranges from about 165 to about 220 grams, more preferably fromabout 180 to about 200 grams. The elastic means about the leg openingpreferably comprises at least two elastic members where the tension onthe member closer to the absorbent batt is greater than the tension onthe elastic member further from the absorbent batt. More preferably theratio of the tension on the members is from about 4:3 to about 3:2. Inthe waist region the preferred tension is from about 330 to about 400grams and more preferably from about 360 to about 380 grams.

Any suitable elastomeric material can be employed for the elastic means52 and 53 that exhibits at least an elongation (defined herein as L_(s)-L_(r) /L_(r) where L_(s) is the stretched length of an elastic elementand L_(r) is retracted length, multiplied by 100 to obtain percentelongation) in the range of 5% to 300% preferably in the range of 25% to200%. Further along these lines, there may be some preferential vagariesin respect of the elasticity of these elastic means relative to thegeometry elected by the designer For example, within the preferred rangementioned above, it has been determined that a most preferred range forthe leg elastic is from about 80 to about 110 for rope elastic and about40 to about 70 for ribbon elastic. Also for the waist elastic thepreferred range is from about 200 to about 250 for rope elastic andabout 60 to about 200 for ribbon elastic. Preferably the elastic has aspring constant of from about 5 to about 40 gms/cm and more preferablyfrom about 15 to about 22 gms/cm.

Various commercially available materials can be used, such as naturalrubber, butyl rubber or other synthetic rubber, urethane elastomericmaterial such as that available from B. F. Goodrich Company under thetrademark TUFTANE, and elastomeric material available from the H.B.Fuller Company under the tradename FULLASTIC. The latter material (seee.g. U.S. Pat. No. 4,418,123) is based upon thermoplastic elastomericcopolymers of the A-B-A type such as those available from Shell Chemicalunder the trademark KRATON which have a rubbery midblock such asbutadiene or isoprene and polystyrene end blocks, and is especiallyuseful because it is a self-adhesive material and can be applied to thelayers of the garment without additional adhesive between the elasticmeans and the layers. The elastic means can be applied to the garment byany suitable means including adhesive bonding, heat sealing or sonicbonding, whichever is appropriate to the specific material selected forthe elastic means.

Adhesion of the elastics 20 and 21 to the liner 16 and to the cover 17is improved by addition of a dissimilar polymer to the liner/covermaterial. This is illustrated by addition of polypropylene to anethylene methyl acrylate cover. It has been convenient to add thedissimilar polymer by addition of a yellow colorant Ampacet containing ayellow pigment and a polypropylene binder. This addition has been foundparticularly effective in EMA when a Fullastic self adhering elastic isused in the training pant.

Preferably, the front and back of the training pant are designated assuch so as to permit the wearer to properly dress himself. This may besuitably accomplished by a label on the interior of the rear portion ofthe training pant.

EXAMPLE

A disposable panty 10 as illustrated in FIG. 1 was constructed in a sizesuitable for use as an infant's training panty with an elasticized waistopening as shown in FIG. 7, elasticized leg openings as shown in FIG. 8and tearaway side seams. The material of the outer cover, or exteriorpanel, of the disposable underpant was a two-layer composite web havingan outer layer of nonwoven polypropylene fibers and an inner layer ofethylene methyl acrylate extrusion coated onto the nonwoven fibrousouter layer. The panty had an interior panel comprising a bodyside linerof spun bonded polypropylene fibers. An absorbent batt of a composite ofpolypropylene microfibers and cellulosic fibers was sandwiched betweenthe exterior panel and the interior panel. Testing of the pantyestablished that it combined the features of liquid-imperviousness dueto the plastic inner layer of the outer cover and a clothlike appearancebecause of the fibrous outer layer of the outer cover. A usefuldisposable training pant was thereby provided that is expected to bewell received by parents and of a type that will aid and encouragechildren going through the toilet training stage.

There has thus been described a disposable underpant including an outercover constructed of two layers of different materials wherein the innerlayer is a plastic material capable of providing the desired degree ofmoisture imperviousness and the outer layer is a nonwoven fibrousmaterial capable of presenting a clothlike or textile appearance andfeel to the underpant. It is believed that the new underpant hereindescribed provides a construction that is an improvement over similargarments of the prior art and that it may therefore extend the use ofdisposable underpants, particularly as a training pant for a child whois ready to graduate from the diaper stage. The texture and feel, aswell as the fit and absorbent capabilies, of the present underpantprovide a disposable undergarment that can function to contain wastefluids and at the same time present a clothlike appearance which couldencourage an infant to discontinue use of diapers. The foregoingdisposable underpant can be more absorbent than a cloth training pantand does not require an additional protective rubber or plastic coveringpant. Because the present garment has elasticized waist and legopenings, a young child of an appropriate age can readily raise andlower the underpant and thereby become accustomed to using the toiletwithout being dependent upon the aid of a parent. The neat tailored lookof the present underpant should be of aid in promoting the use of thetraining pant in lieu of a diaper. Other important potential uses forthe underpant herein described and claimed are an adult menstrualgarment or an adult incontinence garment. The same factors come intoplay in these end uses, since a clothlike disposable underpant having anattractive tailored look is provided that should be particularlyattractive for an adult.

The present invention has been described hereinabove by reference toseveral specific embodiments, but it is expected that those skilled inthe art of manufacturing disposable garments will be able to devisemodifications of the exemplary embodiments and it is intended that theappended claims encompass any such obvious modifications which arewithin the true spirit and scope of the present invention.

We claim:
 1. A three-dimensional disposable underpant for wearing abouta portion of the body, comprising:a disposable liquid pervious innerbodyside liner having opposed marginal side edges, a disposable liquidimpervious outer cover having a front portion, a rear portion, a crotchportion and opposed marginal side edges, and being generallysuperimposed over said liquid pervious inner bodyside liner, anabsorbent batt including a front portion, a rear portion, and a crotchportion generally corresponding to said disposable liquid imperviousouter cover, and disposed between said liquid pervious inner bodysideliner and said liquid impervious outer cover, said liquid pervious innerbodyside liner and said liquid impervious outer cover having respectiveportions of their marginal side edges joined together to form a pair ofside seams, a waist opening, and a pair of leg openings, and elasticmeans extending about said openings for providing elasticity thereto,said liquid impervious outer cover including an inner layer of liquidimpervious plastic material adjacent said absorbent batt and an outerlayer of nonwoven fibrous said inner layer.
 2. The underpant of claim 1wherein the transverse measurement of said crotch portion of saidabsorbent batt is less than about three inches.
 3. The underpant ofclaim 1 wherein the transverse width of absorbent material in saidcrotch portion is 1/4 of the sum of the widest transverse measurementsof said front and said rear portions.
 4. The underpant of claim 1wherein the thickness of said absorbent batt in said crotch portion isfrom about 1.5 to about 5 times the thickness of said absorbent batt insaid front and said rear portions.
 5. The underpant of claim 1 whereinsaid absorbent batt is outwardly bulging in said crotch portion.
 6. Theunderpant of claim 1 wherein said absorbent batt is attached to saidouter cover.
 7. The underpant of claim 1 wherein said absorbent battcomprises a superabsorbent.
 8. The underpant of claim 7 wherein saidsuperabsorbent is confined to a predetermined region within saidabsorbent batt.
 9. The underpant of claim 7 wherein said superabsorbentis disposed in a layer of said absorbent batt immediately adjacent tosaid outer cover.
 10. The underpant of claim 1 wherein said elasticmeans about a respective said leg opening comprises at least two elasticmembers, wherein the tension of said elastic member closest to saidabsorbent batt is greater than the tension of said elastic memberfurthest from said absorbent batt.
 11. The underpant of claim 10 whereinthe ratio of the tension on said closest elastic member to said furthestelastic member is from about 4:3 to about 3:2.
 12. The underpant ofclaim 10 wherein the tension on said leg opening elastic means rangesfrom about 165 to about 220 grams.
 13. The underpant of claim 12 whereinthe tension on said leg opening elastic means ranges from about 180 toabout 200 grams.
 14. The underpant of claim 1 wherein the tension onsaid elastic means about said waist opening ranges from about 330 toabout 450 grams.
 15. The underpant of claim 14 wherein the tension onsaid waist opening elastic means ranges from about 360 to about 380grams.
 16. The underpant of claim 1 wherein said outer cover comprises anon-stretchable material.
 17. The underpant of claim 1 wherein saidouter cover comprises a stretchable material.
 18. The underpant of claim1 wherein said absorbent batt is substantially absent from front andrear panels transversely extending beyond a longitudinal line extendingfrom outside transverse edges of said crotch portion.
 19. The underpantof claim 1 wherein said abosorbent batt comprises a material having adry tensile strength ranging from about 250 ergs/cm² to about 550ergs/cm².